A screen sharing function is known in which it is possible to share a screen on a shared window of one terminal between a transmission side (one terminal) and a reception side(s) (the other terminal(s)) among a plurality of terminals that are remotely positioned by transmitting the screen to the other terminal(s), and displaying the same screen on a shared window(s) of the other terminal(s). This function has been already implemented in many web meeting systems etc.
When the screen sharing function is used in a web meeting system, since terminals have a different sized display, or each user participates in the meeting while executing various applications on each of the screens, there are different sized shared windows among the terminals in many cases. For this reason, there is a mismatch between a shared screen displayed on a transmission side terminal and that on a reception side terminal(s), so that there are cases where the meeting cannot proceed smoothly.
For example, a window sharing system described in Patent Literature 1 controls so that visible areas of shared windows match from each other by changing size(s) of a shared window(s) of the other terminal(s) so as to match size of a shared window of one terminal having an operation right.
A window display controller described in Patent Literature 2, arrangement, size, and title etc. of a shared window on a terminal having an operation right are displayed in a simplified manner on a reception side terminal(s).    [Patent Literature 1]    JP Patent Kokai Publication No. JP-H08-185302A    [Patent Literature 2]    JP Patent Kokai Publication No. JP2000-259535A